Steam explosion treatment with addition of chemicals

• US 6,506,282 B2
• Filed: 02/02/2001
• Issued: 01/14/2003
• Est. Priority Date: 12/30/1998
• Status: Expired due to Fees

• Current Assignee: Neenah Paper Incorporated (Mativ Holdings, Inc.)
• Original Assignee: Kimberly-Clark Worldwide Incorporated (Kimberly-Clark Corporation)
• Inventors: Sun, Tong, Hu, Sheng-Hsin
• Primary Examiner(s): NGUYEN, TAN D
• Application Number:
  US09/775,919
• Publication Number:
  US 20010020520A1
• Time in Patent Office: 711 Days
• Field of Search: 162/4, 162/5, 162/9, 162/21, 162/18, 162/52, 162/247, 162/63, 162/100, 428/357
• US Class Current: 162/5
• CPC Class Codes: D21C 9/004 inorganic compounds
• CPC Class Codes: D21C 9/005 organic compounds
• CPC Class Codes: D21C 9/007 by mechanical or physical means
• CPC Class Codes: D21H 15/04 crimped, kinked, curled or twisted fibres

Abstract

Virgin fibers or de-inked recycled fibers modified by steam explosion in the presence of certain chemicals are able to form handsheets with higher bulk while substantially retaining strength and brightness.

Claims

1. A process for the treatment of cellulosic fibers comprising:

(a) treating an aqueous slurry of individual cellulosic fibers and boric acid with steam at superatmospheric temperature and pressure, wherein said fibers are selected from the group consisting of kraft fibers and deinked fibers; and

(b) explosively releasing the superatmospheric steam pressure to produce curled fibers.

2. The process of claim 1 wherein the aqueous slurry has a consistency of from about 10 to 100 percent.

3. The process of claim 1 wherein the aqueous slurry has a consistency of from about 25 to about 80 percent.

4. The process of claim 1 wherein the aqueous slurry has a consistency of from about 55 to about 75 percent.

5. The process of claim 1 wherein the fibers are treated at a temperature of from about 130°

C. to about 250°

C.

6. The process of claim 1 wherein the fibers are treated at a temperature of from about 150°

C. to about 225°

C.

7. The process of claim 1 wherein the fibers are treated at a temperature of from about 160°

C. to about 225°

C.

8. The process of claim 1 wherein the fibers are treated at a temperature of from about 160°

C. to about 200°

C.

9. The process of claim 1 wherein the fibers are treated at a pressure of from about 40 to about 405 pounds per square inch.

10. The process of claim 1 wherein the fibers are treated at a pressure of from about 40 to about 230 pounds per square inch.

11. The process of claim 1 wherein the fibers are treated at a pressure of from about 90 to about 230 pounds per square inch.

12. The process of claim 1 wherein the resulting curled fibers have a Wet Curl Index of about 0.2 or greater.

13. The process of claim 1 wherein the resulting curled fibers have a Wet Curl Index of from about 0.2 to about 0.4.

14. The process of claim 1 wherein the resulting curled fibers have a Wet Curl Index of from about 0.2 to about 0.35.

15. The process of claim 1 wherein the resulting curled fibers have a Wet Curl Index of from about 0.22 to about 0.33.

16. The process of claim 1 wherein the resulting curled fibers have a Wet Curl Index of from about 0.25 to about 0.33.